cat 10k d6c engine water operating temp

I am rebuilding a pond dam, and have noticed on heavy pushing water temp will get to 210- 215 . not sure what is danger temp, I have after market temp guage on tractor, starts at 100, and ends at 250. thank you keith-52

All depends on the pressure the system holds and the boiling point of the coolant. Just don't want any boiling.

I don't know enough to comment on how the transmission cooler might be interacting with engine heat rejection to possibly cause the temps you are seeing. Might need to drop down a gear.

I would for sure be careful cooling it down before shutting it off when its been running up there. Does it have a D333? Always heard the heads weren't the most durable of CAT designs and are scarce like hen's teeth!

Some of that age tractors had a coolant pressure gauge and the temp gauge had ranges for normal and hot that depend on the pressure.

The red on the gauge would start around 215 F. A 50/50 mix of water and anti-freeze should not boil until 226 F at sea level. So it will be higher than that with a pressure cap. I think your fine.
Muzz